Source for file XMLExporter.class.php

<?php
/**
 * @since 10/17/05
 * @package polyphony.exporter
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: XMLExporter.class.php,v 1.13 2007/09/19 14:04:44 adamfranco Exp $
 */ 
 
require_once("Archive/Tar.php");
require_once(HARMONI."/Primitives/Chronology/DateAndTime.class.php");
require_once(POLYPHONY."/main/library/Exporter/XMLRepositoryExporter.class.php");
 
/**
 * Exports into XML for use with the XML Importer
 * 
 * @since 10/17/05
 * @package polyphony.exporter
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: XMLExporter.class.php,v 1.13 2007/09/19 14:04:44 adamfranco Exp $
 */
class XMLExporter {
        
    /**
     * Constructor
     * 
     * @access public
     * @since 10/17/05
     */
    function XMLExporter () {
        $this->setupSelf();
    }
 
    /**
     * Creates the child lists
     * 
     * @access public
     * @since 10/31/05
     */
    function setupSelf () {
        $this->_childExporterList = array("XMLRepositoryExporter");/*, "XMLSetImporter", "XMLHierarchyImporter", "XMLGroupImporter", "XMLAgentImporter");*/
        $this->_childElementList = array("repositories", "sets", "hierarchy", 
            "groups", "agents");
    }
 
    /**
     * Initializes the export by creating a dir in /tmp/
     * 
     * @param string 
     * @access public
     * @since 10/31/05
     */
    function withCompression ($compression, $class = 'XMLExporter') {
        if (!(strtolower($class) == strtolower('XMLExporter')
            || is_subclass_of(new $class, 'XMLExporter')))
        {
            die("Class, '$class', is not a subclass of 'XMLExporter'.");
        }
        $exporter = new $class;
        $now = DateAndTime::now();
        $exporter->_tmpDir = "/tmp/export_".$now->asString();
        while (file_exists($exporter->_tmpDir)) {
            $now = DateAndTime::now();
            $exporter->_tmpDir = "/tmp/export_".$now->asString();
        }        
        
        mkdir($exporter->_tmpDir);
        
        $exporter->_compression = $compression;
                    
        return $exporter;
    }
 
    /**
     * finds the appropriate key for Archive_Tar
     * 
     * @param string 
     * @return string 
     * @access public
     * @since 10/31/05
     */
    function getTarKey ($extension) {
        switch ($extension) {
            case ".tar.gz":
                return "gz";
            default :
                return "gz";
        }
    }
 
    /**
     * Exporter of All things
     * 
     * @access public
     * @since 10/17/05
     */
    function exportAll () {
        $this->setupXML($this->_tmpDir);
        fwrite($this->_xml, "<import>\n");
        
        foreach ($this->_childElementList as $child) {
            $exportFn = "export".ucfirst($child);
            if (method_exists($this, $exportFn))
                $this->$exportFn();
        }
 
        fwrite($this->_xml, "</import>");
        fclose($this->_xml);
 
        return $this->_tmpDir;
    }
 
    /**
     * creates xmlfile and initializes it
     * 
     * @param string $dir the directory in which the xml file resides
     * @access public
     * @since 10/31/05
     */
    function setupXML ($dir) {
        $this->_xml = fopen($dir."/metadata.xml", "w");
        fwrite($this->_xml, "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
    }
    
    /**
     * Exporter of repositories
     * 
     * Adds repositoryfile elements to the xml, which pass off to individual
     * repository Importers.
     * 
     * @return <##> 
     * @access public
     * @since 10/17/05
     */
    function exportRepositories () {
        $rm = Services::getService("Repository");
        $children =$rm->getRepositories();
        while ($children->hasNext()) {
            $child =$children->next();
            $childId =$child->getId();
            
            fwrite($this->_xml, "\t<repositoryfile>".$childId->getIdString().
                "/metadata.xml</repositoryfile>\n");
            
            $exporter = XMLRepositoryExporter::withDir($this->_tmpDir);
            
            $exporter->export($childId); // ????
            unset($exporter);
        }
    }
    
    /**
     * Compress a directory with status stars. Return the resulting file path
     * 
     * @return string the new archive path.
     * @static
     * @access public
     * @since 12/12/06
     */
    function compressWithStatus () {
        $archiveBaseName = "export_".md5(time()." ".rand());
        
        // Get the number of files in the directory and initialize the status stars
        $status = new StatusStars(_("Compressing the archive"));
        $numFiles = $this->numFiles($this->_tmpDir);
        $status->initializeStatistics($numFiles);
        $filesSeen = 1;
        
        
        $PID = $this->run_in_background(
            'tar -v -czf /tmp/'.$archiveBaseName.$this->_compression.
            " -C ".str_replace(":", "\:", $this->_tmpDir)." . ",
            0, str_replace(":", "\:", $this->_tmpDir)."-compress_status");
        
        while($this->is_process_running($PID))    {
            $lines = count(file($this->_tmpDir."-compress_status"));
            for ($i = $filesSeen; $i < $lines; $i++) {
                $status->updateStatistics();
                $filesSeen++;
            }
            sleep(1);
        }
        // Finish off any last statistics
        for ($i = $filesSeen; $i <= $numFiles; $i++)
            $status->updateStatistics();
        
        // Remove our status file
        unlink($this->_tmpDir."-compress_status");
        
        // Remove the source directory
        shell_exec('rm -R '.str_replace(":", "\:", $this->_tmpDir));
        
        return '/tmp/'.$archiveBaseName.$this->_compression;
    }
    
    /**
     * Run linux command in background and return the PID created by the OS
     *
     * Posted to PHP.net by jesuse.gonzalez@venalum.com.ve on 15-Jul-2005 11:34
     * Addition of output file parameter and inclusion into this class by Adam Franco
     * 
     * @param string $Command 
     * @param integer $Priority 
     * @param string $outputFile 
     * @return integer 
     * @access public
     * @since 12/13/06
     */
    function run_in_background($Command, $Priority = 0, $outputFile = '/dev/null')
    {
       if($Priority)
           $PID = shell_exec("nohup nice -n $Priority $Command > $outputFile & echo $!");
       else
           $PID = shell_exec("nohup $Command > $outputFile & echo $!");
       return($PID);
    }
    
    /**
     * Verifies if a process is running in linux
     *
     * Posted to PHP.net by jesuse.gonzalez@venalum.com.ve on 15-Jul-2005 11:34
     * Inclusion into this class by Adam Franco.
     * 
     * @param integer $PID 
     * @return boolean 
     * @access public
     * @since 12/13/06
     */
    function is_process_running($PID)
    {
       exec("ps $PID", $ProcessState);
       return(count($ProcessState) >= 2);
    }
    
    /**
     * Return the number of files in a directory (recursively) including the directory
     * its self;
     * 
     * @param string $dir 
     * @return integer 
     * @access public
     * @since 12/12/06
     */
    function numFiles ($dir) {
        $numFiles = 1;
        if (is_dir($dir)) {
            if ($dh = opendir($dir)) {
                while (($file = readdir($dh)) !== false) {
                    if ($file != "." && $file != "..") {
                        if (is_dir($dir."/".$file))
                            $numFiles = $numFiles + $this->numFiles($dir."/".$file);
                        else
                            $numFiles++;
                    }
                }
                closedir($dh);
            }
        }
        
        return $numFiles;
    }
}
?>